Q. My mom drinks Slim-Fast and takes levothyroxine for a thyroid condition. She wants to know if it is okay to take them both at once.

A. We suggest she take the levothyroxine at least half an hour, or better an hour, before she drinks her morning Slim-Fast. This diet drink contains minerals that could interfere with the absorption of levothyroxine.

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  1. ss

    taking levothyroxine every morning. can I drink slim fast?

  2. lcm

    Would my 1 dose 325 mg aspirin taken twice a day with my slimfast meal interact? I took as above one morning and first experienced a weak voice & felt a little strange, then after lunch & having another slimfast with 1 325mg aspirin, when I went to get up a few hours later I was bent over double with a heaviness/pressure in my lower abdomen.
    I have experienced a bit milder form of heaviness/pressure ever since (9 months) with no determination of what caused it after going to several doctors. I only take 2 81mg aspirin now and no slimfast. Could an interaction have caused something to go wrong internally? Thank you for your help.

  3. STEVE

    My wife uses levothyroxine. I understand that there needs to be time from taking the medicine and eating. My question is about the time of day to take levothyroxine. Is it ok to take it at bedtime at night so that she does not have to have the waiting period ahead of breakfast upon wakening in the morning?

  4. LEJ

    I too am on a low dose of thyroid medication (Synthroid) per my Dr. I do not feel well, have leg pains and thumb pad pains. Dr. says according to my labs I am on right dose. I felt better on my previous higher dose, no pains. Good question about something else that would raise thyroid level. I have been looking for something also. Any thoughts?

  5. Clara

    My DR. gives me only a low dose of Levithroid to keep me out of the danger zone of low thyroid , is there anything I can take to get my thyroid to produce more hormone on its own , I am concidering changing Drs. Your advice ….. Thank you …

  6. BC

    I take levothyroxine and the directions on the printout from the pharmacy instructs you to take it first thing in the morning on an empty stomach with a full glass of water. I set my alarm and take mine and then go back to sleep for a while.

  7. Judy M

    Will my calcium chews interfere with my levothyroxine or Ursodiol? I take them both before bed on an empty stomach (no problems with that) but will it compromise their effectiveness if I chew my chocolate calcium “candy” at the same time?
    People’s Pharmacy Answer:
    Judy…this is not a good idea since the calcium can interfere with proper absorption of levothyroxine!

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